In the past, a valve stem was manually mounted to a wheel with a stem-inserting tool. Such manual processes are expensive because of the labor and time involved. In addition, operations performed manually are subject to a relatively greater frequency of processing errors in comparison to robot-performed processes.
Several prior art patents disclose processes for mounting a valve stem to a wheel with programmable machines. For example, U.S. Pat. No. 6,481,083 teaches a valve stem assembly line that includes an input conveyor to supply wheels, a locator station positioned at the end of the input conveyor to locate the valve stem aperture defined by the wheel, and a robotic manipulator to grasp the wheel in the locator station and to move the wheel to the mounting station where a valve stem is inserted. U.S. Pat. No. 6,026,552 teaches a spinning device to spin the wheel, an optical sensor to locate the valve stem aperture while the wheel is spinning, and press fitting device that can slide relative to a wheel and insert a valve stem after the valve stem aperture has been located. U.S. Pat. No. 5,940,960 teaches and automatic valve stemming apparatus including a spinning device to spin the wheel, an optical sensor to locate the valve stem aperture, and a valve stem insertion tool to insert a valve stem after the valve stem aperture has been located.
One of the areas of continuous development and research is the pursuit of flexible systems operable to receive and process several differently configured rims. Another area is the pursuit of less costly valve stem insertion devices. Costliness can be defined by the capital investment required for putting the valve stem insertion system on the factory floor as well as the operating cost associated with the system. In pursuit of these goals, it would be desirable to develop a valve stem insertion system having improved flexibility, cost and efficiency.